This is because its easy to imagine just paying two mana and slamming something massive on the board -- and yeah, it will do that sometimes
It will only force a draw if your opponent has a way of preventing damage to themselves, or you are in a multiplayer game with multiple opponents
Creatures (18) 4 Glorybringer 1 Darigaaz Reincarnated 4 Goblin Chainwhirler 3 Verix Bladewing 4 Nicol Bolas, the Ravager 1 Palladia-Mors, the Ruiner 1 Demanding Dragon Planeswalkers (4) Lands (24) Spells (14) Three mana planeswalkers have traditionally been Standard staples, and Sarkhan, Fireblood looks to be yet another
Atraxas mana cost is four different colors of mana, but this is rarely a problem in the Commander format when you have access to so many ramp and mana-fixing spells
Board sweepers fit with both of those goals
Any abilities that care about a counter being removed from or put onto a permanent will apply.